Charcoal briquettes are commonly used in the United States as a source of heat and flavor for outdoor cooking on a barbecue grill or hibachi. The charcoal briquettes are formed from a combination of a combustible carbonaceous material such as charcoal, peat, coal, or other combustible, hydrocarbon-containing carbon source together with a binder, such as corn starch, a non-toxic polymeric material or the like, and compressed under high pressure into briquettes for use as a barbecue fuel. After the composition is formed into briquettes, the briquettes are dried to remove essentially all of the moisture so that the briquettes are capable of ignition. Exemplary of various charcoal briquette compositions and methods of manufacturing charcoal briquettes include the following U.S. Pat. Nos. Dell 5,221,290; Spencer 1,590,706; Wagel 1,618,029; Jaffe 3,089,760; McGoff 3,304,161; Ross 3,709,700; Robertson 3,485,600; Mennen 3,385,681; Onozawa 3,689,234; Swinehart, et al. 2,822,251; Hughes, et al. 4,167,398; and Crace 4,787,914, hereby incorporated by reference.
Surprisingly, it has been found that by including (a) activated carbon and/or activated graphite as a charcoal briquette composition additive, and/or by including (b) non-activated or incompletely activated carbon and/or graphite and a humic acid-containing ore or a humic acid salt-containing ore, oxidation of the carbon and/or graphite source occurs in-situ during the pyrolysis, or heating to a temperature of at least about 450.degree. F., of the charcoal briquette composition to reduce VOCs escaping from the pyrolyzing composition to the atmosphere. The activated carbon and/or activated graphite, initially added in activated form to the combustible carbonaceous composition or added to the composition in the form of reactants capable of activating carbon and/or graphite in-situ, sorbs unexpectedly high amounts of volatile organic compounds (VOCs) that are volatilized from the combustible carbonaceous material--thereby eliminating or reducing the need for VOC-elimination treatment of the gases formed during heating of the carbonaceous material. Such VOC reduction resulting from activated carbon and/or activated graphite formed in-situ is quite unexpected so long as the carbon and/or graphite added to the combustible carbonaceous material for activation in-situ has a low total organic volatiles content (low VOC), at 1800.degree. F. and 1 atmosphere (750 mm Hg) pressure, hereby defined as less than about 10 mg/g, preferably less than about 1 mg/g, more preferably less than about 0.5 mg/g, and most preferably less than about 0.3 mg/g volatiles, at 1800.degree. F. and 1 atmosphere (760 mm Hg) pressure.